Venous flow-through flaps (venous flaps) are useful reconstructive options, particularly in the repair of defects with segmental vessel loss. They are relatively easy to harvest and confer several benefits at the donor site. However, given that they are based on a single central vein, their survival is notoriously unreliable and they are susceptible to ischemia and venous congestion. Various designs have been suggested to improve the circulatory physiology, and hence survival, of venous flap. More recent designs involve adaptations to the arrangement and number of efferent veins draining arterialized venous flaps. The most commonly used classification system for venous flaps, proposed by Chen, Tang, and Noordhoff, does not afford adequate description of these alternate designs. This article offers a classification system that can incorporate all reported modifications to venous flaps. This simple adaptation to the classification system proposed by Chen et al. restores its usefulness in describing modern variations to venous flap design.